South Korea has told members of the United Nations Command that its approval must be granted for any expansion plans, a local media outlet reported Monday.

According to the Kyunghyang Sinmun, Defense Minister Jeong Kyeong-doo sent a letter to the embassies of 16 sending states here in July stating that the US-led UNC would have to obtain approval from South Korea to proceed with its plans to “revitalize” the organization.

South Korean Defense Minister Jeong Kyeong-doo (Yonhap)

In the letter, Jeong is said to have stated that the UNC would have to discuss with Korea adding any country as a member of the command, and that only countries that participated in the Korean War can take part.

As South Korea gears up for the transfer of wartime operational control, concerns have been raised here that the US is trying to strengthen the UNC to maintain its authority over military maneuvers in Korea even after the transition.

Speculations have also been raised that the UNC may be seeking to include Japan as one of the UNC’s sending states, which were later denied.

The Defense Ministry neither confirmed nor denied the report.

“We cannot confirm whether such a document was delivered, as it is a (part of) diplomatic agenda,” Defense Ministry’s spokeswoman Choi Hyun-soo said in a regular press briefing Monday.

“As you all know, the UNC works to understand and respect the armistice agreement in peacetime, while it provides troops of the sending states in contingencies. The role will not change, and the government will respect the role,” she explained.

Aside from South Korea and the US, the UNC has 16 other sending states, including Australia, Canada and Denmark. They provided combat support and service support forces to the UNC during the Korean War, and following the armistice agreement signed in 1953, the countries have committed to providing combat troops, equipment and other forms of support in case of a contingency on the Korean Peninsula.

The US-led UNC has been pushing the “revitalization” campaign that it announced in 2014, and is increasing its staff and senior officials under the scheme.

The UNC earlier said that it does not have any plans to become an operational command.

“Media reports that the US wants to use the UNC as a means to get around OPCON are unfounded,” the UNC spokesperson had told The Korea Herald on Sept. 24. “Any suggestions otherwise are patently false.”